Figure 2.

Effect of divalent cations on Cx30 hemichannel activity. A, membrane currents were recorded on uninjected (Uninj) oocytes (top row) or Cx30-expressing oocytes (bottom row) during application of 100-ms voltage steps from +60 to −140 mV in steps of 20 mV from a holding potential of −50 mV. Membrane currents were recorded in control solution and after 1-min exposure to MgFS, CaFS, DCFS, and DCFS containing 50 μm Gd³⁺ in random order. B and C, summarized I/V curves are illustrated for uninjected oocytes (B, n = 9) and Cx30-expressing oocytes (C, n = 9). D, histogram of currents obtained at −80 mV. E, ethidium uptake after 60-min exposure to control solution, MgFS, CaFS, DCFS, or DCFS containing 50 μm Gd³⁺ (n = 5). Data in I/V curves and in the bar graphs are presented as mean ± S.E. The individual data points are shown by overlaid scatterplots in bar graphs. Statistical significance was tested using repeated measures two-way ANOVA with Bonferroni post hoc test. **, p < 0.01; ***, p < 0.001; ns, not significant.